Effects of complex waste mixtures on hepatic monooxygenase activities in brown bullheads (Ictalurus nebulosus).


Journal Article

Hepatic MFO components (cytochrome P-450, cytochrome b(5), and ethoxyresorufin O-deethylase, EROD) were measured in brown bullheads (Ictalurus nebulosus) inhabiting a creek receiving a complex mixture of organics and trace metals. The activities of these same enzymes were also measured in bullheads from an uncontaminated reference site to assess the relative ability of MFO parameters to serve as a biomarker of aquatic pollution. Bullheads analyzed from the polluted site had lower hepatic microsomal P-450 (p < 0.01) concentrations and similar EROD activities per mg protein as compared to bullheads from the reference site. However, analysis of enzyme turnover ratios revealed greater EROD activity per mg cytochrome P-450 (p < 0.05) in the fish from the polluted site. No difference in cytochrome b(5) activities were observed between the two groups. As compared to the reference site, bullheads collected from the polluted creek had an increased occurrence of lip and lower jaw lesions and liver damage, including elevated liver/body weight ratios. Accordingly, the monooxygenase activities measured in this study were not reliable indicators of chemical pollution or contaminant stress in bullheads in the polluted creek. Further research is needed concerning contaminant interactions, particularly among organic pollutants and metals and their effects on monooxygenase activities.

Full Text

Duke Authors

Cited Authors

  • Gallagher, EP; Di Giulio, RT

Published Date

  • January 1989

Published In

Volume / Issue

  • 62 / 2-3

Start / End Page

  • 113 - 128

PubMed ID

  • 15092340

Pubmed Central ID

  • 15092340

Electronic International Standard Serial Number (EISSN)

  • 1873-6424

International Standard Serial Number (ISSN)

  • 0269-7491

Digital Object Identifier (DOI)

  • 10.1016/0269-7491(89)90182-6


  • eng